Signal transfer system for time division switching systems

摘要

A signalling arrangement for use in PCM systems includes a transfer control for determining whether signalling between exchanges should be transmitted over a speech channel or a signalling channel. If signalling is directed to information for setting up a call, a speech channel is used, whereas supervisory information employs a signalling channel. A marking memory is used having a memory cell per speech channel. A bit is stored in each memory cell for transfer of call set-up information.